Process of combining dialkyl ketones and secondary aromatic amines



, 1T0 Drawing.

Patented June 20, 1933 WILLIAM r. TER- ironsr,

or PAGKANACK LAKE, NEW JERSEY, Assrenon TO THE NAUGATUCK GI'ZEEEICALCOItCPANY, OF NAUGATUCK, CONNECTICUT, A CORPORA- T1031 OF CONNECTICUT'IPROCES SOF CO MBINING DIALKYL KETONE$ AND SECONDARY AROMA'I'IC AMINESThis invention relates to the preparation.

' It is generally known that ketones and pri mary amines may be reactedby heating the same with or without the presence of a catalyst, butthese general procedures are not adapted for bringing about thecondensation of ketones such as acetone and secondary aromatic aminesdevoid of primary amino groups, such as diphenylainine, phenyl betanaphthylamine, p,p-di(beta naphthylamino) diphenyl methane, phenylalpha-naphthylamine, dinaphthylamines, sym-dinaphthyl-p-phenylenediamine, and the like. To condense these classes of materials to producesatisfactory antioxidants it has been found that certain temperatures,pressures and cat al'ysts are necessary. In reacting dialkyl-ketones anddiarylamines, temperatures consid erably in excess of the normal boilingpoint of the lowest boiling constituent to be reacted are required andthe presence of a dehydrating agent such as iodine, which also has acatalytic efi ect on the reaction.

The following examples illustrate the invention:

Ewample].320 pounds of diphenylamine, 220 pounds of acetone, 600 gramsof iodine are heated during 20 hours at approximately 220 C. in an ironautoclave with or without agitation. The pressure is approximately 600lbs. per sq. inch at this temperature. At the end of about 20 hours thecontents are cooled and the excess acetone and the water formed aredistilled ofi. The resulting product is a dark brown liquid which may beused as such or further purified. The reaction time may be shortened byraising the temperature, for example at a temperature of 260 0., areaction time of 12 hours is sufficient. It has also been found thatincreasing the amount of iodine shortens the time of reaction, forexample the use of 1000 grams of iodine allows a satisfactory reactionat 220 C. in about 12 hours.

Example 2.A mixture of 219 grams of phenyl beta naphthylamine, 696 gramsace- 1 tone and grams iodine are heated at ap- Application filedSeptember 24, 1931. Serial IiTo. 564,978.

proximately210 to220 C. during 33 hours in an ironautoclave. Thepressure at this temperature is approximately 600 lbs. per square inch.The crude reaction product is filtered through glass wool and the excessof acetone and the water formed during the reaction are removed bydistillation.

Ewample 3-219 grams of phenyl alpha naphthylamine, 116 grams acetone and1.3 grams of iodine are heated during hours at approximately 210 to 220C. The product after removal of acetone and water is a free flowing oil.

.Emamplc L.The reaction product of acetone andp,p=di-(naphthylamino)ydiphenyl methan'ez The latter compound is firstmade by heating a mixture of one mole of p,pdiamino diphenyl methane and2 moles of beta naphthol' at approximately 260 C. during 20 hours in thepresence ofa dehydrating agent (calcium chloride or iodine). Thechemical constitution of this compound is probably as follows ,A mixtureof 312 grams of p,p-di (naphthylamino) diphenyl methane, 696 grams ofacetone, and lOgramsof iodine is heateddur ing 24 hourszit-approximately 200 C. After removing the excess of acetone and thewater formed during the reaction a solid residue remalns. j

Other ketones that may be used are diethyl ketone, ethyl methyl ketone,mesityl oxide, phorone, diacetone alcohol, etc. The tem* peratureemployed in the reaction should be preferably above 200 C.

Having thus described my invention, what I claim and desire to protectby Letters Patcut is: 1 y

, 1. A process of producing a rubber antioxidant by combining dialkylketones and secondary aromatic amines of the benzene and naphthaleneseries which are devoidof primary amino groups which comprises'reactingtogether in the presence of iodine said ketones and said amines attemperatures above 200 C. which are in excess of the normal boilingpoint of the lowest boiling conaromatic am ne at a temperature above200;

C. and under a pressure substantially above atmospheric pressure in thepresence of iodine. i

3. A process of producing a rubber antioxidant by combiningdialkylketones and diaryl amines whichcomprises reactingto-V gether adialkyl ketone anda non-substituted diaryl amine selected fromthebenzene and naphthalene series at a temperature above 200 C. and undera'pressure substan-V tially above atmospheric pressure in the pres enceofiodine. a o

4. A process of producing a rubber antioxidant by combining dialkylketones and diaryl amines which comprises reacting together acetone anddiphenylamine at a temperature above 200 C. and under a pressuresubstantially above atmospheric pressure in the presence ofiodine.

5. A processof producing a rubber antioxidant by combining dialkylketones and diaryl amines which'comprises reacting together acetone andphenyl-naphthylamine ata temperature above 200 Ghandrunder a pressuresubstantially above atmospheric pressure in the presence of iodine.

-6. process of producing a rubber;antioxidant by combining dialkylketones anl diaryl amines which comprises reacting together acetone andphenyl-beta naphtbylamine in'the presence of iodine at a temperatureabove 200 C. y

7 A process of producing a'rubber antioxidant by combining dialkylketones and diaryl amines which comprises reacting together acetone vandp,p-di(beta naphthylamino) diphenyl methane in the presence of iodine ata temperature above 200 C.

q 8. Avprocess of producing a rubber antioxidant by combining dialkylketones and diaryl amines which comprises reacting together a dialk'ylketone and a non-substituted diaryl secondary amine selected 'from thebenzene and naphthalene series at a temperature offromabout 210 C. toabout 220 C.

and a pressure of about 600 pounds per. sq. in. in the presence ofiodine, and subsequently removing excess ketone and water. I

9.x A process of producing a rubber. antii oxidant by combining dialkylketones and diaryl amines which comprises-reacting together acetone anddiphenylamine at a 'temperature of from about 210 C. to about 220 C.anda pressure ofabout 600 pounds per sq. in. in the presence ofiodine,-and subsequently removing excess ketone and water.

sequently-renioving excess ketone and water.

'11. A process ofproducing a rubber antioxidant by combining dialkylketones and diaryl amines which comprises reacting together acetone and;phenyl beta naphthylamine at a temperature of from about 210 C.

to about 220 C. and a pressure of about 600 pounds per sq. .in. in thepresence of iodine, and subsequently removing excess ketone and Water.

Signed at Montclair, county of Essex, State of New Jersey, this 18th'dayof September,

WILLIAM P. TER HORST.

